overheating WTF!!!

vet111s · Post by **vet111s** » Sat Mar 17, 2007 1:09 pm

Did a run to prestwick and back last night (90 miles) and car was running nicely though checked coolant when I got back and still further losses.
Coolant level is still above minimum (checked this morning before starting car) however when I fired her up the temp reading was flashing and reading 140 degrees!
Could all my coolant have drained from my radiator overnight but hasn't been replaced from reservoir? toying with calling RAC and trying to get her towed to Falkland or as a last (and probaly more expensive) resort MMC in edinburgh.
Any ideas?

PS was informed that MMC Glasgow are no longer a service centre for Lotus!

Look forward to some suggestions that might solve my high temp and hopefully my high blood pressure and heart rate!

Ali

Rich H · Post by **Rich H** » Sat Mar 17, 2007 1:29 pm

Did it show 140 straight away?

If so the blue temp sender is proper fooked. Change them both on spec, they are around £10 each and a PITA to get to (on mine anyway!)

I have got through 3 or 4 sets now in 18 months.

Rich
/elderly S1 faction

vet111s · Post by **vet111s** » Sat Mar 17, 2007 1:32 pm

yep, showed 140 straight off then droppd and waivered between 134and 138

Rich H · Post by **Rich H** » Sat Mar 17, 2007 1:38 pm

Senders first.

They are totally pants. Old rover garage(Mostly now Kia dealers) Landrover dealer or (At a push) Lotus....

Rich H · Post by **Rich H** » Sat Mar 17, 2007 1:39 pm

Oh and check the sender plugs are fitted properly. Could also be a poor earth but I would imagine you would get lots of other problems if it was that bad!

vet111s · Post by **vet111s** » Sat Mar 17, 2007 1:45 pm

With my (very) limited knowledge I would agree with that diagnosis-just started her up again and read 999 degrees-didn't think I was running a nuclear reactor in the back!
anyone got any ideas on parts numbers or should dealers know what I'm talking about if I call?

r055 · Post by **r055** » Sat Mar 17, 2007 3:49 pm

vet111s wrote: anyone got any ideas on parts numbers or should dealers know what I'm talking about if I call?

http://www.elise-faq.info/index.php?tit ... re_Sensors

http://www.eliseparts.com/shop/index.ph ... x&cPath=86

vet111s · Post by **vet111s** » Sat Mar 17, 2007 4:11 pm

Cheers, ordered one of each (ECU and stack). I take it these are the sensors located in the virtually inaccessable area next to at the front LHS of the engine?

any thoughts on how to access them successfully? Was considering trying to get RAC to transport me to MMC cause was going to get the coolant system pressure tested anyway-could get them to fit the sensors there.

As you can see I'm holding up the side of the technically inept when it comes to car DIY-Sorry!!

Rich H · Post by **Rich H** » Sat Mar 17, 2007 5:31 pm

Not a great pic but I'm at work, you can see the brown sensor (ECU) here the blue one is under it. You may not have the coolant pipe running across the top of the engine bay.

Rich H · Post by **Rich H** » Sat Mar 17, 2007 5:32 pm

Oh and there is no easy way of changing it in my experience.

vet111s · Post by **vet111s** » Sat Mar 17, 2007 10:04 pm

Cheers, thanks for the advice. I looks forward to the skint knuckles!

Ali

Dominic · Post by **Dominic** » Sat Mar 17, 2007 11:07 pm

I too am in North Glw... if u need a hand (thou I'm no mechanic

)

robin · Post by **robin** » Sun Mar 18, 2007 8:14 am

Before chaging the brown sensor, test the engine cooling fan cycle on idle - this will prove that the ECU is seeing the correct temperature. Basically the car should heat up, reach ~100C then turn on the fan for a while, repeat. If you have a point thermometer you can test that, or you can test it with your repaired stack display.

You need to understand what the coolant level is supposed to be.

When cold it *SHOULD* be at or very near MIN mark on tank. If you overfill it, it will eject the excess coolant through the header cap until it ends up at MIN. When hot it should end up at or near MAX.

Once you have the coolant level correct at cold I would then replace the header tank cap for good measure.

Cheers,
Robin

Rich H · Post by **Rich H** » Sun Mar 18, 2007 9:27 am

Mine used to sit at half way down the tank and go down to min when hot. Someone said it was the pies expanding or something...

robin · Post by **robin** » Sun Mar 18, 2007 10:45 pm

That does sound a bit BS. Water expands quite significantly when hot. Air compresses easily. The air trapped at the top of your tank should compress when the coolant expands, so the level should go up. not down.

More likely you had some strange air lock behaviour ...

Cheers,
Robin